Refrigeration systems effect cooling by causing a working fluid to evaporate at a lower temperature and to condense at a higher temperature, thereby removing heat from a relatively cold region and rejecting it to a higher temperature region. Conventional refrigeration systems utilize mechanical energy input from a compressor to raise the refrigerant vapor pressure so that vapor is pulled from the evaporator liquid at a cold temperature and then is condensed at a higher temperature such as that of ambient air. Other known cooling/refrigeration systems employ a solid or liquid adsorber or absorber to modify the conditions under which a working fluid will condense. In these systems a working fluid and a sorbent are contained within a sealed enclosure. The sorbent in effect "pulls" vapor from the working fluid at one temperature, and the vapor condenses on the sorbent at a higher temperature. Heat is subsequently used to desorb the working fluid, and thus provides the energy input required for operation of such systems.
While some of the above-described adsorber/absorber systems are available commercially, these systems are generally quite complex, utilizing pumps and many connections. This makes the required leak-tightness difficult to achieve and maintain. Also, such systems may have low coefficients of performance, particularly if solid adsorbents are employed.
It is an object of the present invention to provide an air conditioner/heat pump which is operable with heat energy input but which does not employ a sorbent material.
It is also an object of the invention to provide an air conditioner/heat pump which minimizes susceptibility to leaks and which is simple and inexpensive to manufacture.
It is yet another object of this invention to provide an air conditioner/heat pump which needs little maintenance and is very efficient.